SE452165B - GAS OIL COMPOSITION INCLUDING AN INTERMEDIATE PETROLEUM DISTILLATOR AND A PETROLEUM DISTILLATOR OF AN ADDITIVE TO IMPROVE FILTERABILITY IN COOL - Google Patents

Description

For this reason, said distillation curve is often replaced by the distillation curve according to ASTM D 1160, which has been determined under reduced pressure.

In some of the embodiments of the present application, the classical ASTM curve (M 07 002/70) was used to define the gas oils used, since this curve is still the one most commonly used in industry.

Another limitation on the use of the various known additives to improve the filterability properties in cold of intermediate petroleum distillates is that in combination with the n-paraffins in these distillates they reduce the size of the n-paraffin crystals which occur at low temperature. Although the mechanism for this inhibition of crystal growth is dimly associated with the improvement of the temperature limit for filterability of the gas oils, the sedimentation of already formed microcrystals of paraffins usually accelerates to form a compact sediment at the bottom of storage tanks and tanks in diesel engines.

This phenomenon often causes clogging of the pipelines in cold weather and cutting of the engines at start-up by completely soiling the filters.

It has now been discovered that it is possible to significantly improve the filterability properties in the cooling of intermediate petroleum distillates, especially fractions with a final boiling point above 370 ° C or an initial boiling point above 200 ° C, while avoiding accelerated sedimentation of formed microcrystals of n paraffins. The invention thus relates to a gas oil composition comprising an intermediate petroleum distillate and 20 to 2,000 9 / m3 of petroleum distillate of an additive for improving the filterability properties in the cold consisting of a mixture of a component (A) and a component (B), provided that it the individual concentration of each of the constituents (A) and (B) is not lower than 59 / m3, where the constituent (A) consists of a polymer selected from polyethylene and copolymers of ethylene and vinyl acetate, and where the constituent (B ) consists of a condensation product of at least one cyclic anhydride and at least one N-alkyl polyamine of the general formula .- -vT- s.- - _ ... _ ._ .., ....., ._.._......__...-. f, q- - «,. - _--- ---.- 452 165 n '_ | R -ENH - 3: J-: m2 | n Rf 'I where 1 5 n 3 3, where R represents a saturated or unsaturated alkyl chain containing between 16 and 22 carbon atoms, and where each of the symbols R' and R ", which may be the same or different, denotes a hydrogen atom or a monovalent hydrocarbon group containing 1-3 carbon atoms.

Thanks to the use of the specific additive mentioned above, a clear improvement of the filterability properties in the cold of wide or narrow gas oil fractions to which the additive is added is achieved. This is a surprising result, considering that each of the constituents of the additive combination according to the invention when used alone has practically no effect on the filterability properties of such petroleum distillates.

Component (A) should have a number molecular weight of 500-15,000, preferably 2,000-4,000, and it may have a degree of branching of the needle 7 and 30 groups -CH 3 or -O-C-CH per 100 carbon atoms. The component (A) according to the invention preferably has the following average formula I _ .- = cH 1) 'H3' [Wlzß 'mf (CHÜJ. CH 2 (P where a is an integer between 1 and 11, b is a number between 1 and 11, where a + b is equal to 12, p is a number between 3 and 30, and X is a methyl group or an acetate group.

Component (B) of the additive combination according to the invention is obtained by condensation of at least one cyclic anhydride and at least one linear N-alkyl polyamine.

The useful cyclic anhydrides have the following general formulas: I 452 165 ab Û Ü RS '' Û Raw Û \ "lol / KD“ w / 'ï / * ß “1“ f /' ï ("\ Rz 3 /: za / Y .a7 Rn / RÜ / w /) U (II) (II ') (II "(II"') where each of the symbols R1, R2, R3, Ru, R5, 36, H7: RB, H9, B10, H11 and E12, which may be the same or different, represent a hydrogen atom or a monovalent hydrocarbon group containing 1-5 carbon atoms.

The linear N-alkyl polyamines have the following general formula R 1 IR - {NH - (Ta-n m 2 (III) R 1, where n represents an integer such as 1 3 ng 3, where R represents a saturated or unsaturated alkyl chain containing between 16 and 22 carbon atoms, and wherein each of the symbols R 'and R ", which may be the same or different, denotes a hydrogen atom or a monovalent hydrocarbon group containing 1-3 carbon atoms.

Among the useful linear polyamines of formula III, mention may be made in particular of N-oleyl-1,3-diaminopropane, N-stearyl-1,3-diaminopropane, N-oleyl-1-methyl-1,3-diaminopropane, N- oleyl-2-methyl-1,3-diaminopropane, N-oleyl-1-ethyl-1,3-diaminopropane; N-oleyl-2-ethyl 1,3-diaminopropane, N-spheryl-methyl-1,3-diaminopropar, N-stearyl-2-methyl-1,3-diaminopropane, N-stearyl-1-ethyl-1,3 -diaminopropane, N-stearyl-ε-ethyl-1,3-diaminopropane, N-oleyl-dipropylenetriamine and N-stearyl-dipropylenetriamine and mixtures of these compounds.

The condensation of the anhydrides of formula II with the amines of formula III to prepare the compound (B) can be carried out without the use of solvents, but preferably an aromatic hydrocarbon having a boiling point of between 70 and 250 ° C, e.g. toluene, a xylene, diisopropylbenzene or an aromatic petroleum fraction with the desired distillation range.

The preparation is carried out in the following manner. The polyamine is introduced portionwise while maintaining the temperature between 30 ° C and 45 ° C. Thereafter, the temperature is allowed to reach 120 DEG-220 DEG C. to remove the water formed, either by means of an inert gas such as nitrogen or argon, or by azeotropic distillation with the selected solvent. The reaction time after the addition of the polyamine is between 2 and 8 hours, preferably between 3 and 6 hours.

The above-mentioned constituents (A) and (B) are according to the invention particularly interesting when it comes to improving the filterability properties in the cold of intermediate petroleum distillates, in particular so-called broad gas oil fractions with a final boiling point above 37,000 e.g. between 370 and ü50 ° C, and so-called narrow gas oil fractions with an initial boiling point according to ASTM above 20,000, e.g. between 220 and 23000. When each of the constituents (A) and (B) is used alone in such petroleum distillates, no effect or at most a very limited effect is achieved. Thus, it appears that each of the components (A) and (B) exerts a synergistic effect on the properties of the other component. The mechanism of the synergistic effect has not yet been clearly established.

The desired effect is usually manifested when the weight ratio of component (A) to component (B), or the weight ratio of component (B) to component (A), is at least 1: 100, preferably at least 1:20.

In order to obtain a clear improvement of the filterability properties in cold of the intended gas oil fractions, the additive combination of components (A) and (B), which are used in a mutual weight ratio of between 1: 100 and 100: 1, should preferably be used. in a weight ratio of from 1:20 to 20: 1, is added to the gas oil fractions in a total concentration of component (A) plus component (B) of 20-2000 g / m 3 gas oil, provided that the individual concentration of each one of the constituents (A) een (s) ieke is less than 5 g / m3.

In some cases, an improvement in the filterability properties can be observed already at a total concentration of component (A) plus component (B) which is lower than 20 g / m3.

However, concentrations of this order of magnitude are usually insufficient to give a very strong effect on the temperature limit for filterability.

The optimum total concentration of the additive combination according to the invention is usually in the range 50-500 g / m 3.

To prepare the gas oil compositions of the invention, it is possible to add the components (A) and (B) directly to the 452 165 s gas oil by a simple mixing operation. _.

However, it is often advantageous to introduce constituents (A) and (B) in the form of pre-prepared "parent solutions", using two different solutions in the same solvent or in two different solvents, or using a solution of both constituents. The solvent or solvents may be, for example, aromatic solvents such as toluene, xylene, diisopropylbenzene and aromatic petroleum fractions having the desired distillation range.

The "parent solutions" can e.g. contain 20-60% by weight of additive.

It is remarkable that the additives according to the invention, which in contrast to classical additives are active in broad petroleum fractions, i.e. fractions with a distillation interval of e.g. 150-37006 and higher, and are always active when used in a narrow petroleum fraction with a distillation interval of e.g. 250-360 ° C and higher, i.e. a narrow fraction from which the light fraction (kerosene) has been removed, and at the same time inhibits the sedimentation of n-paraffins in the additive gas oils at rest, even though the n-paraffins are the heaviest n-paraffins. in the distillable fraction of the crude oil.

This result is all the more surprising as it is the light fraction which exerts a very favorable influence on the filterability temperature and on the solvation of the paraffins.

The additives according to the invention thus make it possible without inconvenience to replace a light hydrocarbon fraction with a heavy fraction, which is very interesting from an economic point of view.

The invention is illustrated by the following non-limiting examples.

Examples 1-3. These examples are intended to show the effect of the additives according to the invention on various gas oils, the synergistic effect of the constituents of the additives, and the inhibitory effect on the sedimentation of microcrystalline paraffins in gas oils, which have been added with additives and kept at rest at low temperature.

As component (A) the following two polymers were used (A1). An ethylene polymer having an average molecular weight of 2725 and a degree of branching of 9 methyl groups per 100 carbon atoms.

(A2) A copolymer of ethylene and vinyl acetate having an average molecular weight of 1750 and a vinyl acetate content of 28%. As component (B), a condensation product of maleic anhydride and N-oleyl-1,3-diaminopropane prepared under the above reaction conditions was used.

The treated gas oils (petroleum distillates) and their properties are listed in Table I below.

Table I Distillation Distillation according to ASTM Percent stripped Density at in jursprung. at 35000 15 ° C (kg / l); Begynise- f slut-: boiling point _§ _ boiling point. . . . , .. I ÉARAMco 198 ° c Å hoh ° c 87 o, 8h17 š l 'i: sAFANnA 2oo ° c _ = 378 ° c 86 o ßsoo i I, = äxxnxux 193 ° c 392 ° c 87 oßuzs The effect of the various additives the temperature limit for filterability is given in Table II below, which also shows the synergistic effect of the two constituents in the additive mixture according to the invention.

Table II of the order 'Temperature limit for filterability. (9C) ._ FUISPIUIIQ. | - v f Inger (A1). (A2); (B) f Biananing Biananing 1 aaaitiv .._, __, (A1) + (B) * (A2) + (B) * ¿ARAMCO Å + 7 + 6 'o + 6 É - 6 - 12' SAFANIYA I + hoi - 5 + h § - 8 - 13 ñinkux I + 1 - 1 ¿- h 'I _0. -.7. _ - 10 * Mixture containing 2Ä0 ppm (g / m3) of component (A) and 60 ppm of component (B).

Example H. In this example, the best weight ratios between the two constituents of the additive according to the invention are determined.

The components used (A1) and (B) were the same as described in Examples 1-3.

The treated gas oil is a broad fraction obtained by distilling a crude oil of Aramcoeursprung. The distillation range according to ASTM D 1160 for this gas oil has an initial boiling point of 187 ° C and a final boiling point of ÄN1 ° C.

The distillation range according to the classical ASTM distillation curve has an initial boiling point of 93 ° C and a final boiling point of 40906. 452 165 s The total concentration of additives is 300 ppm.

The results obtained are summarized in Table III below.

'Table III Sample No.' (A) (ppm) E (B) (ppm) 'Temperature limit for filter- 1 i .. 1. i. .Barity (OC) 1 0 § o + 7 2; 300 É i f 3; 3 * zho i 60 3 - M I Ä 180 É 120 _ Ä 5 § 150 I 150 l ~ 5 6 120 i 180 _ - 3 7 .O. É _. 300Ä.-. . . . ..Ä ..Å..I Û f'I. . . . _.

The results in Table III show that the additive according to the invention is effective within a wide range of weight ratios between the components. The ingredients are preferably used in a weight ratio of 75:25.

Example 5. This example is intended to illustrate the effect of the concentration of the additive according to the invention on the temperature limit of filterability of a treated gas oil.

The gas oil treated is a broad fraction obtained by distilling a crude oil of Safaniya origin. This fraction has an initial boiling point of 18 ° C and a boiling point of 392 ° C according to the classical ASTM curve.

The additive used is a mixture of component (A2) and component (B) (see examples 1-3) in a weight ratio of 75:25.

The results obtained are summarized in Table IV below.

'Table IV Concentration of 1 additive (g / m3).' 0 1 175. ....., l35o 700 Temperature limit for filterability in (OC) 0 8 - 12 - 15 Example 6. Three different gas oils I, II and III, whose distillation range according to ASTM D 1160 is 162-ü62 ° C, 18U-H2H ° C and 229.5-359 ° C, respectively, are treated with three different additives 1, 2 and 3 at a concentration of 350 ppm. Additives 1 and 2 consisted of classic, commercial additives, and additives 3 consisted of an additive according to the invention. The results obtained are summarized in Table V below.

Table 5 in Temperature limit for filterability (° C) É 1 Gas oil I T Gas oil II! Gas oil III no additive E + 3 + U - 1; additive 1; - 1 I + 2 _ - 1 z '- f f: Additive 2 2 + 2; + 5 - 1 iAdditiV 3 \ Ö .... f11. . ., ..f12. Example 7. The purpose of this example is to illustrate the effect of the additive according to the invention on different, broad or narrow gas oil fractions, which have different initial boiling points and end boiling points according to ASTM's classic distillation curve. The results obtained are summarized in Table VI below.

Table VI Vi Gas oil Temperature limit for filterability (° C) _Distillation density No additive 300 ppm additive interval (° c) at 15 ° c_. __ I 179-aan o, a37o o - 9 173-390 o, 838o -1 -13,, 178-390 o, Bho7 + 2 - 3 II 1 5 178-396 o, Bh2o + 2 - 6 5 22 - 60 This example is intended to illustrate the inhibitory effect of the additive according to the invention on the sedimentation of crystallizing n-paraffins in a gas oil fraction which is kept at rest at low temperature.

Three pronures with a volume of 100 cm3 are filled with a gas oil fraction, which according to ASTM's classic distillation curve has an initial boiling point of 19300 and an end boiling point of H09 ° C. This gas oil also has a cloud point (temperature at which crystals of n-paraffins begin to appear) of + 11 ° C, a temperature limit for filterability of + 7 ° C and a pour point of -18 ° C.

Claims (6)

No additive is introduced into the first test tube. In the second test tube, 300 ppm of a classical, commercial additive is introduced. 300 ppm of an additive composition according to the invention are introduced into the third test tube. The three test tubes are hermetically sealed and then kept immobile in a cold chamber at -10 ° C for a period of one week. After this week, the degree of sedimentation is determined, ie. what percentage of the paraffins have fallen out. The results obtained are summarized in Table VII below. i r t. Test tube no. 3 (áddítiv.enl..uppf.) .1S%. . . . . _. ._ f Test tube No. 1 Test tube No. 2; (no additive) ... (classical.additive) 50% ..._ '°.', 95% Ä The results show that the classical additive accelerates the sedimentation of the paraffins in the examined gas oil compared with the sedimentation in the untreated gas oil, while the additive according to the invention significantly retards the sedimentation at the same time as it improves the filterability properties of the gas oil (see Example H). P a t e n t k r a v Gas oil composition, characterized in that it comprises an intermediate petroleum distillate and 20 to 2,000 3. 9 / m petroleum distillate of an additive to improve the filterability properties in the cold consisting of a mixture of a component (A) and a component (B), provided that the individual concentration of each of the components (A) and ( B) is not less than 59 / m3, where component (A) consists of a polymer selected from polyethylene and copolymers of ethylene and vinyl acetate, and where component (B) consists of a condensation product of at least one cyclic anhydride and at least one N- alkyl polyamine of the general formula RI IR -fma - (c) âL- ma I 3 n 2 RI! "WP 452 165 11 where 1 5 n 5 3, where R represents a saturated or unsaturated alkyl chain containing between 16 and 22 carbon atoms, and where each of the symbols R 'and R", which may be the same or different, 1 denotes a hydrogen atom or a monovalent hydrocarbon group containing 1-3 carbon atoms. Composition according to Claim 1, characterized in that the weight ratio between components (A) and (B) is from 1: 100 to 100: 1. Composition according to Claim 2, characterized in that the weight ratio between components (A) and (B) is from 1:20 to 20: 1. Composition according to any one of Claims 1 to 3, characterized in that the total concentration of constituents (A) and (B) is 50-500 g / m 3 of petroleum distillate. 5. A composition according to any one of claims 1-4, characterized in that the average molecular weight of the component (A) is between 500 and 15,000. Composition according to any one of claims 1-5, characterized in that the gas oil fraction is a broad fraction q: having a boiling point according to ASTM higher than 370 ° C, preferably between 390 and 450 ° C; or that the gas oil fraction is a narrow fraction with an initial boiling point according to ASTM of at least 200 ° C, preferably between 220 and 230 ° C. - .4-.33 al!